The present invention relates to curved projection screens, in particular projection screens that are curved in three dimensions.
Projection screens that are shaped like a sphere or part of a sphere, so-called dome screens or immersive screens, can be used in a variety of fields, such as simulation, training, high end gaming, immersive display for virtual and augmented reality, etc. It is crucial for the quality of the projected image to have a smooth and bulge-free surface in order to provide a high image quality. This can be obtained by implementing the screen in a rigid material that resist deformation that could arise from draft, non-uniform tension between fixation points, its own weight etc. It is common to implement such rigid screens by dividing them into smaller segments, in order to facilitate logistics. In this way it is possible to use standard trucks or containers to carry the screen, or to be able to pass through a standard door or window when bringing the screen into a building. The dimensions of the opening width of a “standard door” are typically in the range 750 to 800 mm. For example, the Housing Standards Review—Illustrative Technical Standards Developed by the Working groups from the UK Department for Communities and Local Government dated August 2013 details requirements for communal entrances, both internal and external A communal entrance door to a building containing flats (or other dwelling types served by a communal entrance or doors) should have a clear opening width of at least 800 mm. All external gates, openings or doorways within an approach route should provide a minimum clear opening width of 850 mm. Secondary entrance doors, for example within a lobby or porch, should provide a minimum clear opening width of 800 mm. For a private entrance area a door should have a clear opening width of at least 800 mm. The doorway to any habitable room, the kitchen, and the room containing the WC should provide a minimum clear opening width of 750 mm.
At the installation site, the screen is mounted by putting the segments together. A visible seam between the screen segments would disturb the projected image, therefore these seems are concealed with additional fill up and painting. To assemble and finish the screen surface on-site requires a substantial amount of labour and equipment. The final coatings or paints should also be applied by specially trained people.
U.S. Pat. No. 5,724,775 discloses a multi-pieced portable projection dome that is constructed from a plurality of rigid panels.
U.S. Pat. No. 6,712,477 discloses a non-deployable hemispherical projection dome.
CN2932438 discloses a method of manufacture of a cylindrical rollable projection screen.